Harmonic diffeomorphisms of noncompact surfaces and Teichmüller spaces

Let g : M -> N be a quasiconformal harmonic diffeomorphism between noncompact Riemann surfaces M and N. In this paper we study the relation between the map g and the complex structures given on M and N. In the case when M and N are of finite analytic type we derive a precise estimate which relates the map g and the Teichmüller distance between complex structures given on M and N. As a corollary we derive a result that every two quasiconformally related finitely generated Kleinian groups are also related by a harmonic diffeomorphism. In addition, we study the question of whether every quasisymmetric selfmap of the unit circle has a quasiconformal harmonic extension to the unit disk. We give a partial answer to this problem. We show the existence of the harmonic quasiconformal extensions for a large class of quasisymmetric maps. In particular it is proved that all symmetric selfmaps of the unit circle have a unique quasiconformal harmonic extension to the unit disk

Extremal maps of the universal hyperbolic solenoid

We show that the set of points in the Teichmuller space of the universal hyperbolic solenoid which do not have a Teichmuller extremal representative is generic (that is, its complement is the set of the first kind in the sense of Baire). This is in sharp contrast with the Teichmuller space of a Riemann surface where at least an open, dense subset has Teichmuller extremal representatives. In addition, we provide a sufficient criteria for the existence of Teichmuller extremal representatives in the given homotopy class. These results indicate that there is an interesting theory of extremal (and uniquely extremal) quasiconformal mappings on hyperbolic solenoids.Comment: LaTeX, 15 page

Convex regions in the plane and their domes

We make a detailed study of the relation of a euclidean convex region $\Omega \subset \mathbb C$ to $\mathrm{Dome} (\Omega)$. The dome is the relative boundary, in the upper halfspace model of hyperbolic space, of the hyperbolic convex hull of the complement of $\Omega$. The first result is to prove that the nearest point retraction $r: \Omega \to \mathrm{Dome} (\Omega)$ is 2-quasiconformal. The second is to establish precise estimates of the distortion of $r$ near $\partial \Omega$

On the Zeros of Functions in the Bers Space

We present some results on the distribution of zeros of functions in the Bers space Q(D), showing how the distribution depends on the bounds of the growth of │ƒ(z)│ HS │z│ƒ → 1, for ƒ Є Q(D). We also exhibit an open and dense subset, M C Q(D), which has the property of uniform control over the number of zeros in disks of hyperbolic radius l containes in D

Isometries between the spaces of L^1 holomorphic quadratic differentials on Riemann surfaces of finite type

By applying the methods of V. Markovic [7] to the special case of Riemann surfaces of finite type, we obtain a transparent new proof of a classical result about isometries between the spaces of L^1 holomorphic quadratic differentials on such surfaces

Heart rate and lactate responses to taekwondo fight in elite women performers

The purpose of this study was to examine heart rate (HR) and blood lactate (LA) concentration before, during and after a competitive Tae kwon do (TKD) fight performed by elite women performers. Specifically, we were interested to see weather HR and LA responses to competitive fight were greater than to TKD or karate exercises published in scientific literature. Seven international-standard women TKD fighters participated in the study. HR was recorded continuously throughout the fight using Polar Vantage telemetric HR monitors. LA samples were taken before and 3 min after the fight and analysed using an Accusport portable lactate analyzer. At the beginning of the fight, HR significantly increased (p<0.01) from pre-fight values of 91.6±9.9 beats min-1 to 144.1±13.6 beats min-1. During the whole fight the HRmean was 186.6±2.5 beats min-1 and remained significantly elevated (p<0.01) at 3 min into recovery. HR values expressed as a percentage of HRmax averaged during the whole fight at 91.7±2.6% respectively. LA concentration significantly increased (p<0.01) 3 min after the fight and averaged 82% of LApeak values measured after the VO2max test. Results of the present study indicate that physiological demands of competitive TKD fight in women, measured by HR and LA responses, are considerably higher than the physiological demands of TKD or karate training exercises. The observed HR and LA responses suggest to us that conditioning for TKD should generally emphasise high-intensity anaerobic exercise

The effect of encapsulated amount of caffeine on the mechanism of its release from hydrogels based on poly(methacrylic) and casein

Researchers are making everyday efforts to develop new drugs or improve present ones in order to enhance therapies of various diseases, especially serious ones like cancer. Drug delivery systems (DDS) are one of the solutions for safer and more efficient therapy. Hydrogels based on poly(methacrylic acid) (PMAA) are extensively investigated as DDS due to their nontoxicity, biocompatibility and pH sensitivity. Many chemotherapeutics are poorly watersoluble, so it is quite challenging to encapsulate them into highly hydrophilic PMAA. In our previous study we overcome this limitation by modifying PMAA with amphiphilic casein and demonstrated that poorly water-soluble model drug – caffeine can be successfully encapsulated and released in control manner from these samples (H hydrogels). In present study we go step forward and investigated how the change in the amount of encapsulated caffeine affect the mechanism of caffeine release from the H hydrogels in medium with pH of 6.8 (which simulates the environment in human intestines). Commonly used models for the analysis of kinetics of drug release from hydrogels: Ritger-Peppas, Higuchi and Kopcha model are employed for the analysis of the mechanism of caffeine release. Presented results indicate that it is possible to adjust the manner and mechanism of drug release by changing the amount of encapsulated drug, due to which the H hydrogels can adapt to the unique requirements of the therapy

Imaging the charge transport in arrays of CdSe nanocrystals

A novel method to image charge is used to measure the diffusion coefficient of electrons in films of CdSe nanocrystals at room temperature. This method makes possible the study of charge transport in films exhibiting high resistances or very small diffusion coefficients.Comment: 4 pages, 4 jpg figure

Analysis of kinetics of poorly water-soluble drug release from hydrogels based on poly (methacrylic acid) and casein with different crosslinker amount

Nowadays, humanity are faced with many challenges which affect health of people all around the globe (such as climate change, new diseases and/or already present ones for which cure has not been found yet – cancer). The efforts of researchers on the field of drug delivery systems bring everyday novel tools for safer and more effective therapy. pH sensitive hydrogels based on poly(methacrylic acid) are recognized as materials with huge potential for controlled release of drugs. The encapsulation and controlled release of many chemotherapeutics is quite challenge due to their poorly water-solubility. In our previous research we overcome this problem by modifying hydrophilic pol(methacrylic acid) with amphiphilic casein and showed that prepared material have potential for encapsulation and controlled release of poorly watersoluble model drug – caffeine (PMAC carriers). In present study we deepened further our research and employed various models: Ritger-Peppas, Higuchi and Kopcha model to analyze how the change of crosslinker amount affect the mechanism of release kinetics of caffeine in medium with pH of 6.8 (which simulated the environment in human intestines). Obtained results showed that only by changing one parameter such as crosslinker amount it is possible to fine tune the type of drug release mechanism, due to which the PMAC carriers would be able to respond to the specific demands of therapy

Chloroplast pigments in post-fire-grown cryptophytes on Vidlič Mountain (Southeastern Serbia)

In this study the content of chloroplast pigments (chlorophyll a, b, a+b, and carotenoids) in the leaves of Geranium macrorrhizum L., Doronicum columnae Ten., Aegopodium podagraria L. and Tussilago farfara L. from a beech forest that had undergone fire on Vidlič Mountain was determined. The same species of plants from a place that had not been exposed to fire were taken as controls. Chloroplast pigments were determined from acetone extracts of these plants spectrophotometrically. In the first year after the fire the content of chlorophyll a, b and a+b in Geranium macrorrhizum L. and Doronicum columnae Ten. was greater than in the plants not exposed to fire. The results were the opposite for Aegopodium podagraria L. and Tussilago farfara L. These differences can be attributed to the different physiology of the plants and consequently their different adaptation patterns. The carotenoid content was higher in the plant species at the fire site than in the area not exposed to fire